As shown in U.S. Pat. No. 3,868,157 (hereinafter the “‘157’ patent”) incorporated herein by reference, it is known to provide a rotary filing cabinet system having what is known as a starter cabinet followed by one or more of what are known as adder cabinets arranged in line with the starter cabinet. In this prior art system, as shown in FIG. 1 of the '157 patent, two adder cabinets, for example, may follow to the right of the starter cabinet. Each of these two adder cabinets has a smaller front width than a front width of the starter cabinet, even though the rotor containing shelves for each filing cabinet has the same front width. Although the starter cabinet has a left and a right front panel assembly lying to the left and to the right of the rotor, the two adder cabinets only have a right front panel assembly at the right side of the rotor. In the two adder cabinets, no left front panel assemblies are provided since sufficient spacing exists for the rotor in the two adder cabinets to turn without the corners of the rotor hitting the adjacent rotor, since no internal sidewalls are provided between the starter and the first adder cabinets, or between the two adder cabinets.
With this prior art unit, floor space is saved with such an arrangement of starter plus two adder cabinets since the two adder cabinets have a narrower width than the starter cabinet.
As shown in the '157 patent, both the starter and the two adder cabinets have a same height. However, if it is desired to have a short adder cabinet lying between a tall starter cabinet and another tall adder cabinet, it was known in the prior art that all three of the short adder cabinet, the tall starter cabinet, and the tall adder cabinet must be of a full size width which is the same for all three cabinets, assuming the rotors of the three cabinets all have a same width. This has the disadvantage of requiring more floor space.